feat: display departure times and search time in CET, regardless of which timezone the users is located in

src/modules/search-time/selector/index.tsx

@@ -8,6 +8,7 @@ import {
 } from '@atb/translations';
 import { SEARCH_MODES, SearchMode, SearchTime } from '../types';
 import style from './selector.module.css';
+import { setTimezoneIfNeeded } from '@atb/utils/date';
 
 type SearchTimeSelectorProps = {
   onChange: (state: SearchTime) => void;
@@ -22,8 +23,10 @@ export default function SearchTimeSelector({
 }: SearchTimeSelectorProps) {
   const { t } = useTranslation();
   const [selectedMode, setSelectedMode] = useState<SearchTime>(initialState);
-  const initialDate =
-    'dateTime' in initialState ? new Date(initialState.dateTime) : new Date();
+  const initialDate = setTimezoneIfNeeded(
+    'dateTime' in initialState ? new Date(initialState.dateTime) : new Date(),
+  ) as Date;
+
   const [selectedDate, setSelectedDate] = useState(initialDate);
   const [selectedTime, setSelectedTime] = useState(() =>
     format(initialDate, 'HH:mm'),
@@ -47,11 +50,23 @@ export default function SearchTimeSelector({
   };
 
   const resetToCurrentTime = () => {
-    setSelectedTime(() => format(new Date(), 'HH:mm'));
+    const newState = {
+      mode: selectedMode.mode,
+      dateTime: setTimezoneIfNeeded(new Date()).getTime(),
+    };
+    setSelectedTime(() => format(newState.dateTime, 'HH:mm'));
+    setSelectedMode(newState);
+    onChange(newState);
   };
 
   const resetToCurrentDate = () => {
-    setSelectedDate(new Date());
+    const newState = {
+      mode: selectedMode.mode,
+      dateTime: setTimezoneIfNeeded(new Date()).getTime(),
+    };
+    setSelectedDate(new Date(newState.dateTime));
+    setSelectedMode(newState);
+    onChange(newState);
   };
 
   const isPastDate = (selectedDate: string) => {

src/page-modules/assistant/client/journey-planner/index.ts

@@ -9,6 +9,7 @@ import { swrFetcher } from '@atb/modules/api-browser';
 import useSWRInfinite from 'swr/infinite';
 import { createTripQuery, tripQueryToQueryString } from '../../utils';
 import { useEffect, useState } from 'react';
+import { formatLocalTimeToCTE } from '@atb/utils/date';
 
 const MAX_NUMBER_OF_INITIAL_SEARCH_ATTEMPTS = 3;
 const INITIAL_NUMBER_OF_WANTED_TRIP_PATTERNS = 6;
@@ -37,7 +38,17 @@ export function useTripPatterns(
   fallback?: TripData,
 ) {
   const [numberOfTripPatterns, setNumberOfTripPatterns] = useState(0);
-  const query = createTripQuery(tripQuery);
+  const query = createTripQuery(
+    tripQuery.searchTime.mode === 'now'
+      ? tripQuery
+      : {
+          ...tripQuery,
+          searchTime: {
+            ...tripQuery.searchTime,
+            dateTime: formatLocalTimeToCTE(tripQuery.searchTime.dateTime),
+          },
+        },
+  );
   const { data, error, isLoading, isValidating, size, setSize } =
     useSWRInfinite<TripApiReturnType>(
       createKeyGetterOfQuery(query),

src/utils/date.ts

@@ -20,8 +20,10 @@ import humanizeDuration from 'humanize-duration';
 import { DEFAULT_LANGUAGE, Language } from '../translations';
 import dictionary from '@atb/translations/dictionary';
 import { TFunc } from '@leile/lobo-t';
+import { FALLBACK_LANGUAGE } from '@atb/translations/commons';
 
 const humanizer = humanizeDuration.humanizer({});
+const CET = 'Europe/Oslo';
 
 export function parseIfNeeded(a: string | Date): Date {
   return a instanceof Date ? a : parseISO(a);
@@ -150,8 +152,9 @@ export function formatToClock(
   showSeconds?: boolean,
 ) {
   const parsed = parseIfNeeded(isoDate);
-  const rounded = !showSeconds ? roundMinute(parsed, roundingMethod) : parsed;
-  const seconds = showSeconds ? ':' + format(parsed, 'ss') : '';
+  const cet = setTimezoneIfNeeded(parsed);
+  const rounded = !showSeconds ? roundMinute(cet, roundingMethod) : cet;
+  const seconds = showSeconds ? ':' + format(cet, 'ss') : '';
 
   return formatLocaleTime(rounded, language) + seconds;
 }
@@ -354,3 +357,17 @@ export function formatTripDuration(
 
   return { duration, departure, arrival };
 }
+
+export function setTimezoneIfNeeded(date: Date): Date {
+  if (Intl.DateTimeFormat().resolvedOptions().timeZone === CET) return date;
+  return new Date(date.toLocaleString(FALLBACK_LANGUAGE, { timeZone: CET }));
+}
+
+export function formatLocalTimeToCTE(localTime: number) {
+  const offset = getOffsetTimezone();
+  return 3600000 * (offset - 1) + localTime;
+}
+
+function getOffsetTimezone() {
+  return (-1 * new Date().getTimezoneOffset()) / 60;
+}